John k



@gutter gratta gnent flirte JOHN K. CALDWELL, 'OF ALLEGHENY CITY, PENNSYLVANIA.

.i Letters Patent No. 73,433, dated January 21, 1867.

IMPROVED BRICK-DRYING APPARATUS.

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TO ALL WHOM II MAYCONCERN: p

Be it known that I, JOHN'K. CALDWELL, olf the city of Allegheny, in the county of Allegheny, andSt'ate of Pennsylvania, have invented a new and useful Improvement in Apparatus for Drying Brick andother articles; andI do hereby declare the following to be a full, clear, and exact description thereof, reference being had to the accompanying drawings, making a part of this specification', in which Figure I is a perspective view of my improved oven.

Figure 2 is a vertical transverse section through the front part of the oven, in the line x, hg. 3; and

Figure 3 is a horizontal section along the line y y, hg. and extending back a little .beyond the rear endy of the furnace.

Like letters of reference indicate like parts in each.

The nature of my invention consists'in the arrangement of an improved heating-apparatus for heating air,A

in connection with an -ovcn for-drying lumber, brick, vegetables, or other articles requiring such treatment, such heating-apparatus consisting of a coil or coils of pipe, a heating-chamber, and furnace, so arranged, substantially as hereinafter to be described, as to admit cold air, heat the same, and discharge it, highly heated, into the drying-house, for the purposes above named.

To enable others skilled in the art to make and use my invention, I will proceed to describe its construction vand how used.

A is a drying-house, of any approved size or shape, though I usually make it wide enough to admit one or more carsten the tracks a a, and long enough to secure the capacity desired. The drying-house has doors B at either end.

Under the track a a, I place a furnace or furnaces, with grate-bars b, a roof, c, arched or of other desirable shape, doors d, and elsewhere closed on all sides, except at the apertures e, whence smoke-pipes e lead back to the ilues C. I usually put in a number of such apertures, e, and a corresponding number of pipes, c', in order to increase the amount of heat-radiating surface.

In each furnace, and in such position as to be acted on by the fire, I arrange a coil of pipe, z', open at one end, z", into the external atmosphere, and at the other end, o, by branches, o', if desirable, opening into the drying-house, The inner end, 0, being higher than the outer end, i', a current of air will be carried through the pipes z', and discharged into the drying-house at a high temperature.

To secure an increased amount of heating-surface, I make a chamber, m, over and on as many sides as may be found practicable, with registers, n, in front or beneath, or both, as shown in the drawing. The roof, c, of the furnace should be such as readily to transmit heat to the nir in the chamber m. Such chamber, m, I make open-in the rear, so as to discharge the air admitted through the registers' n into the drying-house at a high temperature. In this way I pass several currents of air over and in close contact with a largeramount of heating-surface, and discharge the air, thus heated, into the drying-house, where, coming in contact with the articles to be dried, it evaporatcs the moisture therefrom. At the same time, the hot air from the pipes-c', as well as the heat from the smoke-pipes e', co-operates to produce the same result.

- In order that the hot air from the drying-house may not become surcharged with moisture, I interpose a floor,f, between thc oven proper and the roof A. Some portions of this floor consist of wire gauze, p, perfo 'rated plate, or other similar material, on which I place a layer of sawdust,p, or other material of like character' which absorbs or takes up the moisture from the hot air of the furnace, and so keeps it in a it condition for doing its work. r

In order that the air of the d'ryingfhouse may be carried off as fast as it becomes partially cooled, and a constant current be kept up from the furnaces, through the oven, AI place a ventilator, g, at suclllpart of the drying-house as will secure this result. I make it usually of considerable height, to secure thc better draught. At its tcp I make a damper, L, with which to regulate or stop the flow of air at pleasure'. Two or more such ventilators,f, may be constructed with each drying-house, if so preferred or found necessary, and usually I so arrange them relatively to the furnaces, which may be placed at any desirable part ofthe oven, so as to secure a current or currents of air through the oven for the purposes described.

With the coils :3f-pipe, t', I sometimes use a fan-blower, for the purpose of forcing through them au increased quantity of air.

The advantages I claim are a cheap construction of furnace and drying-house, one well adapted for the uses designed, and free from many'of the objections and inconveniences usually experienced. I also secure a. large heating-surface, over which to pass the air te be heated, by which the heut generated in the furnace is economieally applied to the purposes in view.

What I claim as my invention, and desire to secure by Letters Patent, is-

l. The arrangement of u coil of pipe, fr', over the {ire-space of the furnace of a drying-house or oven, substantially as and for the purposes hereinbefore set forth.

2. A furnace so constructed, with floublem'alls, :1s to have a. chamber, m, such chamber being furnisheu with registers, n, or other equivalent device for admitting air, and opening, byany suitable apertures, into the drying-house or oven, substantially as and for the purposes hereinbcfore set forth.

3. The ventilators g, so arranged, relative to the hot-air chamber m :ind coil or coils of pipe z', as to secure a. current or draught of air therefrom through the drying-house or oven, substantially as and for the purposes hereinbefore set forth.

In testimony whereof, I, the said JOHN K. CALDWELL, have hereunto set my hand.

JOHN K. CALDWELL,

Witnesses:

A. S. NICHOLSON, GEO. H. CHRISTY. 

